


The Many Uses of Demonic Beast Materials

by Anonymous



Category: Fire Emblem: Fuukasetsugetsu | Fire Emblem: Three Houses
Genre: Dubious Consent, M/M, Sex Pollen, Sylvix is only in the epilogue, Top Ashe Duran | Ashe Ubert, Wild Demonic Beasts Give You More Than Just Umbral Steel
Language: English
Status: Completed
Published: 2020-05-11
Updated: 2020-07-26
Packaged: 2021-03-03 04:35:45
Rating: Explicit
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 5
Words: 3,195
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/24118879
Author URL: https://archiveofourown.org/
Summary: While fighting a demonic beast, Caspar is covered in a strange liquid.It's probably fine.Fill for the FE3H Kink Meme
Relationships: Caspar von Bergliez/Ashe Duran | Ashe Ubert, Felix Hugo Fraldarius/Sylvain Jose Gautier
Kudos: 60
Collections: Anonymous





	1. Chapter 1

**Author's Note:**

> It's so refreshing to see a fandom kink meme active. This is a fill for:  
> https://3houseskinkmeme.dreamwidth.org/476.html?thread=156636
> 
> Hope you enjoy, anon.

“Ragh,” Caspar shouted as he charged the demonic beast. He smiled as he felt his axe pierce the beast’s tough hide. Just one more hit would likely bring the creature down. Just one more blow and he could claim victory.

He grabbed the hilt of his axe and yanked to free it from the beast, but it didn’t budge. He looked up in time to lock eyes with the beast – it was clearly less than pleased to have an axe stuck in its side.

The creature drew up its head, and Caspar could feel the heat radiating from the beast’s body. The beast’s neck glowed orange as it prepared its fire attack.

Just before Caspar could see if he was actually flammable (he wanted to experiment if he was once, Linheart had told him it was a bad idea), Caspar heard the thwack of an arrow piercing skin, and saw a sniper's bolt protruding from the creature’s neck. The beast made a hiccup sound as it tried to breath its fire onto the battlefield, but instead, with a gurgle, it began to topple over. Caspar barely had enough time to leap out of the way before it hit the ground with a thud.

Caspar glared at Ashe as he approached. “I had that one.”

Ashe smiled back, “Just doing my part, Caspar. Also, I believe that means I’m leading with two beasts today? I guess that means I’ll be feeding our cat tonight.”

“You wish, there’s still plenty of beasts, and this battle is far from over.”

“Of course,” Ashe said smiling, “you ready for the next one?”

Caspar started to nod, but abruptly stopped, “Wait a sec, need to get my axe. Teach just got it for me,” he said as he hauled himself on top of the beast. “It should be right… here,” he shouted the last word triumphantly, as he grabbed the handle and began to yank.

“Ugh,” he grunted before the axe abruptly pulled free of the beast, sending Caspar toppling.

Ashe did his best not to laugh at the now-sprawled Caspar, who was covered in what appeared to be demonic-beast goo. Ashe walked over and hid a grimace – the stuff, whatever it was, had a sickly sweet odor.

Caspar inhaled, before shouting, “REALLY? I just polished this armor.” Ashe did his best not to laugh at his friend’s pouting expression. He was probably going for sullen, but Ashe found it cute more than anything else.

“If you two are done messing around,” a voice from above them echoed, “the professor wants us to move to support Sylvain and Felix against the enemy commander.” They looked up in time to see Ingrid’s Pegasus fly off.

Ashe decided to take pity on Caspar, and held out his hand. “Come on, I suppose you can help feed Sir Whiskers too.”

Caspar glared, then took the hand and pulled himself up. “That’s not his name and you know it,” he said as he began making his way toward the sounds of the battle. Ashe smiled, and followed behind a moment later.


	2. Chapter 2

If asked, Ashe, in his usual kind-to-a-fault way, would say was happy to take whatever watch no one else wanted. In reality, Ashe always preferred the first watch. The ability to get an uninterrupted sleep appealed to the archer. And, truth be told, only the most stupid of bandits would try attacking the camp while twilight still provided some visibility.

Ashe rolled his shoulders as he surveyed the camp, feeling the tension release. While the battle hadn’t been too strenuous, his draw arm would definitely be sore in the morning. Still, he was happy the professor had picked him to help with the bandits. They were attacking towns near Lonatto’s old lands…

Ashe shook his head quickly as he tried to dislodge the thought of his adoptive father from his mind. He took a deep breath, and tried to latch onto something happier… like Caspar sprawled on the battlefield, covered in monster goo. Ashe smiled at the thought. Through dinner, the oddly sweet smell still lingered on the warrior, even after Ingrid and Dudue grabbed him and hauled him into a nearby lake.

Ashe paused as he though over the dinner. Caspar was quiet. Caspar is never quiet.

Were he and his classmates perhaps a bit too harsh in their teasing? Ashe frowned. He had been really pleased when the blue-haired boy had joined their class, he hoped he hadn’t made Caspar want to return to the Black Eagles.

Ashe sighed, feeling the guilt begin to take root. Right or wrong, he’d have to go to Caspar and apologize. After taking a quick look around and confirming, yep, still no enemies, he began walking toward Caspar’s tent.

When he arrived, he whispered, “Caspar? Are you awake?”

Ashe listened for a response but heard none. He thought he heard a strange rubbing sound, like leather rubbing against itself, but it was faint, probably just the tent in the evening breeze.

“Caspar, I wanted to talk about what happened at dinner today. Can I come in?”

Again, no response. Ashe couldn’t tell if the fighter was sulking, or already asleep. Regardless, it didn’t matter, he told himself. He wasn’t going to just barge into the tent - he’d just have to speak to the fighter in the morning. As he turned to leave, he heard a soft “…ah…” come from within the tent. Ashe paused.

It couldn’t hurt to just poke his head in, and make sure his friend was alright. He could check that Caspar was feeling ok, that he knew they were happy to have him in their class, and then he would return to his watch.

‘You just want to see if he sleeps shirtless,’ a traitorous voice said in his mind. Ashe ignored it. He was checking on his friend because it was the right thing to do. Steeling himself, he poked his head in the tent… and his mouth promptly fell open.

Caspar was indeed shirtless – his flushed torso was covered in a fine sheen of sweat. His gaze drifted lower, and saw Caspar rubbing his still-clothed crotch. He brain didn’t even register that the fighter hadn’t bothered to take off his gauntlets, too busy staring at the outline of Caspar’s length, which straining against the fabric of his pants.

It was at that point Ashe’s sense of shame caught up with him as he flushed, pulling his gaze away. He was about to mumble an apology about intruding and dash out when he looked at his friend’s face… something was off. Despite the small size of the tent, Caspar had failed to notice him. His cheeks were flushed, as though he had drunk too much, and his head seemed unsteady, lolling to one side, then the other.

“Caspar,” Ashe asked, his concern beginning to override his previous embarrassment. Caspar let out a groan in response.

“Ashe… hot…”

Ashe moved closer – Caspar’s pupils were blown wide, and he seemed to be having issues recognizing the archer. Ashe placed a hand on his shoulder to try to steady him.

‘He’s warm,’ Ashe’s traitorous mind supplied.

“Caspar, do I need to get Mercedes?” Ashe really hoped he didn’t. The thought of exposing sweet, innocent Mercedes to… whatever this was made Ashe blush all over again.

Caspar didn’t respond for a moment. But his gaze seemed to be tracking Ashe, now, at least. The blue-haired boy smiled.

“Caspar?”

Caspar moved quickly, grabbing Ashe’s hand on his shoulder and using it to pull the archer toward him. Ashe only a moment to gasp before he felt Caspar’s lips crash against his.

It took several seconds for Ashe’s brain to catch up. As best as he could tell, yes, Caspar was kissing him, and yep, the warrior was beginning to grind against his leg too.

It took every bit of self control Ashe had to push Caspar off him and get out a short, “Caspar, please…”

Ashe tried to push the other boy away. He really did. Something was wrong with his friend, and it would be wrong to continue. He knew this. He said this to himself. But another, darker voice got louder in his mind, with each kiss, with each thrust… And when he saw Caspar beneath him, panting, begging, desperate, that voice rang through him.

“It’s about time.”


	3. Chapter 3

**Notes for the Chapter:**

> Sorry for the long wait. Just one more chapter after this.

He really should have been going to Mercedes. Or Byleth. Or anyone else. That would have been the thing for a just knight to do.

Instead, Ashe pulled Caspar against him, and enjoyed the feeling of the other’s warm body against his. He smiled as he felt Caspar shift and try to rut against his leg. Ashe pushed against his chest, “Let’s maybe get your gauntlets off first?”

Caspar paused for a moment, so Ashe assumed he understood – but just as he reached for Caspar’s arm he was pulled into another tight embrace.

“Caspar, I can’t help you until we deal with your armor,” Ashe said, growing frustrated. He was impatient too, but he didn’t think the sharp edges on those gauntlets would be conducive to a fun and safe time.

Besides, if he wasn’t going to go to Mercedes now, he certainly didn’t want to go later and explain he was bleeding because, while making out with his clearly intoxicated friend, they forgot to remove the sharp weapons he was wearing.

Caspar had just enough presence of mind to pout, “but… it’s so hot. I need you now… please.”

Ashe swallowed as the words went straight to his groin. He felt himself twitch each time Caspar let out another breathy “please.”

“Alright,” Ashe said, moving back to allow Caspar to hug him while thrusting against his leg. As he moved to kiss Caspar, he very carefully moved his hand into his pocket, grabbing the spare bowstring he always carried. Shamir had told him once a good archer would never be caught dead without a spare bowstring – he was pretty sure this wasn’t what she had envisioned but was thankful all the same.

Ashe deepened the kiss, gently nipping on Caspar’s bottom lip, while guiding the warrior’s hands behind his back. It only took him a moment to wrap the cord around – thankfully the gauntlets prevented Caspar from feeling anything as he worked, and by the time Caspar realized he couldn’t move his arms, they were secured behind him.

“Ashe…” Caspar whined, as he tried to get free.

“It’s alright, I’m going to help you,” he said as gently as he could. He reached behind Caspar to the straps securing the sharp edges weapons of the gauntlets and pulled them off, before moving down Caspar’s body, his hands quickly found the edge of the warrior’s trousers, and promptly pulled the fabric down. Caspar had apparently skipped undergarments today – Caspar’s penis smacked against his stomach, the tip already glistening. Ashe resisted the urge to lick it as he continued pulling Caspar’s pants down, letting them rest around his ankles – further binding the blue-haired fighter.

As he sat on Caspar’s legs, Ashe took a moment to appreciate the sight before him – Caspar’s hands were tied behind his back, his eyes were still unfocused, but the litany of “please” and “hot” had slowed. Ashe gently ran a finger down from his neck, over his abs, to ghost over the short teal hair near his waist, before leaning down and kissing Caspar’s neck.

Ashe did his best to savor this, the feel of Caspar in his hands, the warmth, the soft gasp he made when Ashe licked a spot on his neck. He moved downward, exploring the hard muscle of the warrior’s chest, feeling the fullness in his hands, the way Caspar’s nipple felt his palm. In a moment of tactical brilliance that would have made Byleth proud, he surged up and captured Caspar’s lips again, just before he grabbed the nub with his hand and pinched, stifling Caspar’s shout as his body shivered beneath him.

Ashe smiled wickedly as he pulled away. “Did you enjoy that?” He wasn’t expecting to get a response, but Caspar nodded so furiously Ashe was afraid he’d sprain something. “Good boy,” he teased before giving the other nipple a flick. “If you’re good, you’ll get relief soon,” he said as he began to pull his own shift over his head.

Caspar stared hungrily as Ashe’s pale stomach was revealed to him. Before he even finished pulling it over his head, Caspar was upon him, kissing the freckles on his stomach. Ashe planned to push him back, he was supposed to be helping Caspar, but he paused as his hands brushed against Caspar’s hair. He hadn’t expected it to be so soft…

Caspar seemed to calm for a moment – he drifted from kissing to gently nuzzling against Ashe, before he let out another whine.

“Ashe…. Please….”

Ashe froze and pulled his head back to meet Caspar’s eyes. They were still unfocused, but they at least seemed to be tracking him.

“Alright, I got you,” Ashe said, quickly lifting his own hips up to yank his own pants quickly off him. Despite the cold of the tent, he was harder than he ever remembered.

With a quietly mumbled, “I’m sorry,” he lined up his penis with Caspar’s and thrust. The friction was perfect. Caspar moaned beneath him, and tried to find Ashe’s lips again.

Ashe continued thrusting against Caspar, wrapping his calloused hand around them both. Just has he felt himself get close, he paused, and looked at Caspar’s face. As wrong as it was, he wanted to remember this.

Caspar’s face was still flushed. He did look so pretty, Ashe, thought, but was distracted by seeing Caspar’s lips move.

“Ashe, please.”

Ashe came, and Caspar followed a single stroke later. He felt the warmth of Caspar’s spend on his hand as he fell onto Caspar’s chest, panting.

He'd handle the repercussions soon, just after he took a few moments to catch his breath. He felt his eyes closing - Caspar's chest was so warm and comfortable... He could enjoy this, just for a few more minutes.


	4. Chapter 4

Ashe couldn’t remember a time he had slept so well. Despite the lumpy bedroll, despite that he clearly had woken up well before the sun, despite that his pillow was moving, he felt great. He wasn’t on breakfast duty, so he could sleep a bit—

Ashe’s eyes shot open. 

He was sprawled over Caspar. The previous night came back to him in waves – each memory crashing over the archer. The sound of Caspar’s begging, the was Caspar looked at him, how warm he was…

Ashe had never done well with the cold. It brought up memories of sleeping in dark alleys, before Lonato adopted him. He felt himself leaning back toward Caspar before he stopped himself – but he wanted to. Goddess, he wanted to just lie back down, and ignore this, if only for a few more minutes.

He had likely destroyed their friendship – to say nothing of what Byleth or Dimitri would do to him when they found out.

So, if he was a dead man, why not enjoy his last few moment, he thought.

“Uh… morning? Ashe froze. He slowly turned to see Caspar’s staring at him. Ashe stayed silent, preparing himself for whatever came next. 

“So, uh, about last night…” Caspar trailed off. 

“I’m sorry!” Ashe blurted out. “I’m sorry,” he said again. “What I did… it was inexcusable. And I’m happy to hand myself over to Byleth or Dimitri or Seteth, or whatever you think is best.” He looked up at Caspar, who’s normally expressive face had, for once, gone blank. He waited a few moments before continuing, “I don’t know what possessed me to take advantage of you like that, but…”Ashe hung his head. “I’ll go wait outside, and give you some privacy to change, and then we can go to Byleth together.”

As Ashe made to get up, an arm crashed against his back, pinning him against the warrior.

“You’ll do what I think is best?” Caspar asked. 

Ashe swallowed. “Yes. I’m at your mercy.” He closed his eyes and braced for a blow.

“Good,” Caspar said, before pulling Ashe into a kiss. 

It took Ashe a moment before he realized the pressure on his lips. Another before he opened his mouth, enjoying the feel of Caspar’s tongue against his own. 

“I want this,” Caspar said, breaking the kiss. “Can I? I mean, I know it’s probably not the story-book chivalrous, romance you probably wanted. Ingrid told me I should try going on a quest for you, but Byleth didn’t want me to go off on my own, and besides that would be a quest for Garreg Mach more than you, so I…”

“Wait, you wanted to do this,” Ashe pauses, making a gesture between them, “before… whatever happened yesterday?”

“Well, Ingrid and Sylvain both told me to start with dinner, or something more romantic, before—” 

“That wasn’t what I meant!”

“But,” Caspar continued, “yeah, I had thought about it. You, uh, look pretty good in some of your riding outfits.” Caspar paused, before asking, “You want this too, right? This isn’t some knightly-obligation now that you’ve “deflowered” me or something?”

Ashe wasn’t sure if he was elated or mortified by this entire conversation – perhaps a bit of both? “There, uh, was a reason I didn’t call Mercedes when I saw you last night.”

“Good,” Caspar said, before pulling Ashe toward him. “Then it’s settled. We’re boyfriend now!” He smiled at the archer before pulling the blanket to cover them.

Ashe’s guilt still wasn’t completely satisfied. “You’re sure?” Ashe blurted. “I mean, last night…”

“Yes, Ashe, I’m sure,” Caspar smiled. “Though next time, could you use something other than bow string? My wrists are a bit sore.”

It took Ashe a few seconds to grasp the implications, before he smiled, and nestled against Caspar’s warmth. “Sure.”

“I have a boyfriend now.” Caspar said, as he began to drift off.

“Yes, you do.” Ashe chucked. “And so do I.”


	5. Chapter 5

**Notes for the Chapter:**

> I've had this little side-scene bouncing around in my head since I was writing chapter 3. Hope you enjoy.

_Earlier that night:_

“I’m telling you we need to check it – it could be a threat!” Felix shouted over his shoulder as he quickly walked toward Caspar’s tent. 

“Fe, maybe we shouldn’t—” was as much as Sylvain managed to get out before Felix threw the tent flap open, revealing a very naked Ashe atop an equally naked Caspar (he also might have been bound – Sylvain wasn’t sure). 

Felix stood there, his mouth opening and closing. If they weren’t sleeping, Sylvain would have been laughing.

“I told you, Fe, that’s not the sound of someone in distress. You’d know that if you didn’t insist on gagging me every time we—” Sylvain was once again interrupted, this time by a sword to his neck. While the sword was unpleasant, it was worth it to watch Felix flush scarlet in front of him. He gave his best disarming smile.

“Feh” Felix huffed as he sheathed the blade and stormed off. 

Sylvain quickly glanced at his classmates. While he’d tease Ashe mercilessly later, he couldn’t hold back a smile. Sylvain quickly leaned in and threw a blanket over them, before securing the tent flap and running after Felix.


End file.
